It is often difficult to tear a film by hand because of necking and elongation during tearing. For improvement of the hand tearability of film, a cut or a notch such as V notch, is often formed on the film.
Patent Document 1, for example, discloses as the hand-tearable film a porous polyolefin resin film obtained by drawing a film of a polyolefin resin blended with filler crosswise monoaxially. The porous polyolefin resin film is said to be superior in hand tearability in one direction.
Alternatively, Patent Document 2 discloses a polyamide-based heat-shrinkable film containing an aliphatic polyamide polymer and an aromatic polyamide polymer that has a particular linear cutting efficiency, hot water shrinkage rate and variability in thickness. The polyamide-based heat-shrinkable film is said to be superior in linear cutting efficiency.
[Patent Document 1] Japanese Unexamined Patent Application Publication No. 2002-52843
[Patent Document 2] Japanese Unexamined Patent Application Publication No. 2007-100000